Telephone-receiver.



E. SCHWARTZ. TBLBPHoNB REGBVER APPL Patented Aug. 2, 1910.

ICATION IILBD APR.20, 1907.

To all 'whom i may concern:

UNITED STATES I)ATENT OFFICE.

EDWARD SCIIWARTZ, OF ANTWRP, BELGIUM, ASSIGNOR OF ONE-THIRD TO EDXVARD E. CLEMENT, 0F WASHINGTON'. DISTRICT OE COLUMBIA.

TELEPHONE-RECEIVER.

Specification of Letters Patent.

Patented Aug. 2. 11910.

/ l Application filed April 20. 1907. Serial No. 369265- Be it known that I, EnwAnn bcnwanrz, a subject of the King of Belgium, residing at Antwerp, l'elgiuin,l have invented certain new and useful Improvements in Telephone- Reeeivers, of which the following is a specilication, reference being had therein to the accompanying drawing.

My invention relates to `telephone reeelvers.

The object of the invention is to provide a casing for the operating parts of the receiver Which will be cheap to construct,`neat' in appearance and of suilicient strength to withstand the hardest usage to which reeeivers are. subjected, also to properlyv insulate the parts from the. user`s hand.

Heretofore, telephone'receiver shells have been constructed of hard rubber and while the rubber has many advantages, it also has many disadvantages, the principal among` which is its frangiblhty. Most re` ceivers have their operating parts held in operative position in tl1e.asing by the hard rubber cap. and il this or the main casing becomes broken, the parts are exposed, and are liable to fall apart.` Again, all metal receiver shells have been proposed, rl`his type also has its disadvantages and, while it possesses sutlicient strength to withstand the hardest use to which it may be subjected,it hasI no insulating property and users oll the receiver are liable to get shocks from accidental Contact. ol' operative parts with the shell. By combining the advantages of both types and eliminating their disadvantages` l am enabled to constructl a practical and ellicient receiver.

Briefly stated, my invention comprisesl an inner hard drawn seamless brass shell over which is vulcanized a hard rubber coating. The cap is made in the same, manner and the threaded portion of thc shell and the cap are ol a metal suitable l'or such purpose and are. secured to the lining of each by soldering or shrinking.

My invention is illustrated in thc acc-ompanying drawing, wherein l show a longitudinal central Section oit thc receiver casing with the operating parts in t'ull lines therein.

ln the ligure, l designates a permanent magnet carrying at its upper end the wind ings Q with their pole pieces lllocated atljacent the usual diaphragm t. which in this instance is supported upon a non-magnetic cup 5 held upon the end o'f' the permanent magnet in any suitable manner. 'lhe terminals are secured to an insulating block t3 and project up through the cup 51 where the)y are connected to the'windings 2.

Surrounding tht` operating parts oit' thc receiver is a hard drawn seamless brass shell 7 open at both ends and flared at one end thereof to conform with the usual shape otl receivers of this type. The flared end of the receiver is also flanged at S to receivt` a threaded metal reinforcing ring 9 secured to-the shell iu any suitable manner as b'v shrinking or soldering. (')vcr the shell T is tlowcd or molded an insulated coating ltl, preferahl)v of hard rubber. but which may bc of any material adapted to thoroughtvl insulate the parts. such as porcelain, enamel, etc. 'l`he cap 1l is l'ormed in the same manner and is provided with a lining l2 of brass or other suitable material, which has connected to it a threaded rino' 13 so as to e11- gage with the ring il carried by the shell i'. 'l`he ring 123 may either be tormed separately l'rcm the lining 1;' or may be an integral part thereof. lt is shown hcrcin as a separate part. 'l`ht` cap is provided with an opening or openings 1| which extend through thc rubber ll and thc lining 1Q for the passage ol' sound wavesy from the diaphragm. .\.t thc opposite cud ol the rc ceivcr the shcll is apcrtured at l5 so as to register with an apcrturt` lt) in the insulating coating l() to permit the passage of the cord conductor.

ln constructing the article l may use several different methods, but l herein describe onl \v two. the first one ot which involves the Jfollowing process: disk of metal` such as brass or other suitable material, having a consistency adapt ed to be easily worked. together with retpti`V site strength, is placed in a die press and gradually worked in the forni of a evlinder through successive stages o'f operation. fully understood by thosc versed iu the art. .\ttcr thc cylinder is formed with one llaring cnd it is tapped out at l5. The shcll is then placed in a tlangiug machine and the tlange :t is l'ormed on its upper end so as to receive and limit the movementI of a ring t which may bc either soldered or swtated upon theshell. This ringmay he either threaded prior to its attachmentwith the shell, or, it may be threaded afterward, according to the desire of the manufacturer. The shell is then placed in a mold and rubber is molded around it and is vulcanized with the aperture 16 registering with the aperture 15. The lining 12 of the cap is formed of sheetmetal and is stam ed up in one o eration and the threaded ring 13 attache thereto. The rubber is then vulcanized over the Whole in any desired manner.

The second method 'em' loys the following process: A metal tube o suitable diameter is flared out at one end Where it is flanged in a flanging machine or by a spinner. The opposite end has an inwardly extending flange formed in any suitable manner which defines the aperture 15. The cap is made in the same manner as described in the former process and each part has then flowed over its surface a coating of enamel, porcelain, or other suitable insulating material.

It will be understood that the materialand mode of application of the insulating material described in the first process might be used with the shell described in the second process or the material alid mode of applying the insulating material described in the second jurocessniight be used with the shell described iii the first process, the kind of insulating material being immaterial for the results produced.

It will be seen from the above that I have provided a receiver shell which will withstand the hardest usage without destroying the ,article for practical purposes. The rubber may become broken and fall away from the metallic shell but the operating parts will still remain intact'. This is not liable, however, because with a receiver' constructed in this manner the insulating coating is uniformly and continuously sup yorted and does not readily break or chip olli.)

I have described in a simple way the method of manufacturing the article so that it may be clearly understood, but I do not wish to be limited to the exact procedure, nor do I desire to be limited to the exact construction show n, as some modifications might be resorted to without departing from the scope of the invention, and I consider and contemplate Such modifications as within the purview of the appended claims. l

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. In a telephone receiver, a continuousintegral thin metallic shell having a flared end, a reinforcing ring secured to the flared end, ka metallic cap, and a ring connected with the cap so that it will engage with the said reinforcing ring on the shell, means tosecure `said rings and thereby the shell and cap together, insulating material molded over the shell, and an insulating coating for 'the cap. l

2. A telephone receiver comprising a continuous integral thin metallic shell having a -flared end, a vthreaded reinforcing ring secured to the flared end, a .metallic cap, and

a threaded ring connected with the cap so that the convolutions thereof will engage and lock with the threads of the reinforcing ring, insulatingA material molded over the lshell, and an insulating coating for the cap.

In testimony whereof I affix my signature in presence of two Witnesses.

EDWARD SCHWARTZ.'

Witnesses z En. SU'iMANN, J. HOLAMINE. 

